Re: [Alsa-user] No sound from streaming audio + ALSA

[Paulo M. C. A. <pmc...@ya...>]

Gianluca Cecchi wrote on Dec, 15:

[...]

> you also said that you are able to play cd or local audio files with xmms.
> Could you verify this with xine, too, using alsa driver (as it seems you
> already do,
> from config)?

Trying to do what you suggested, I discovered a cool xine option: 
--debug-report[=MRL]. It plays the MRL appending the verbose output on 
BUG-REPORT.TXT. I also discovered how to disable audio visualization which was 
causing xine to eat up almost 80% CPU and resist being terminated. I'm 
starting to like xine, thanks to you.

I was collecting all the info that you suggested when something new came up.  
I've got a thread going on in alsa-devel, "Tips on debugging ALSA driver 
snd_es18xx", and Clemens Ladisch has just discovered what seems to be a bug in 
the driver handling of 16-bit data. He asked me to put this in ~/.asoundrc:

pcm.u8 {
	type plug
	slave.pcm {
		type linear
		slave {
			pcm "hw:0"
			format U8
		}
	}
}

and now:

1. aplay produces sound on both speakers
2. xmms and gxine produce sound only on the left speaker

[...]

> In case of success, the problem I think is to search in rtsp filter /
> decoder than alsa itself.
> And so you should change / upgrade / optimize your rtsp player
> In your command you get:
> 
> xine: found input plugin  : rtsp streaming input plugin

I can't understand this: gxine allows me to play rtsp streams, xine doesn't.  
"Open Location" displays sources: FILE, VCD and VCDO, and I couldn't find a 
way of keying in an MRL. Now I remember: this is why I gave up on xine and 
started using gxine instead.

> You can try with xine-check command to see if it shows good flags for rtsp
> and its demuxer.

I've just learned that xine-check depends on xine-config, but it's not in the  
same package (maybe I should raise a bug against the Debian package). I found 
it in another package, but this package pulls another 10MB of other packages, 
so I'll just leave it for the moment.

> You can try http://trisk.acm.jhu.edu/rtspget/, or download locally the
> stream with xine command line
> option if your version support it (*appending '#save:/path/to/file' to a MRL
> (e.g. `xine rtsp://blah/asdf.rm#save:/tmp/asdf.rm')*

I tried:

xine -v 'rtsp://wbgo.advance.net/broadcast/real3/encoder/frodo/frodo.rm#save:/home/paulo/bug/alsa/wbgo.rm'

but it just starts and stops immediately, without any errors.

[...]

> Just my opnion; as I am not a developer of anyone of these layers.....

But you do know a lot, at least has taught me a lot.

> Tipically, the more I read about audio and video, the less it seems that I
> know ;-)

I'm still at that stage of knowing so little that I usually don't even know 
what to ask.

Thank you so, so much, Gianluca, for teaching me all these things about sound 
& xine. You've been really helpful. I'm more than interested in if you have 
any other suggestions and ideas.

Paulo